All spread spectrum radars are subject to adverse interference due to man-made sources. The prior art contains a wide variety of methods for operating chirp radars in an interference environment. However, experience has demonstrated that such methods decrease the operating performance of the radar system. Accordingly, it would be desirable to have available a radar system which can adapt to interference by coding its chirp frequencies to transmit and receive only in that portion of the spectrum where there is no interference. By so doing, a chirp radar system could operate at optimum performance levels.